This invention relates to an automatic pouring furnace, and more particularly, to a control apparatus for a pouring furnace which reads from a memory and automatically adjusts pressure and time variables for a pouring operation as a function of the particular mold to be filled in the pouring operation.
In automatic pouring furnaces, metal or other material is melted by means of induction heating. The molten metal is stored within a reservoir and urged under a base pressure through a throat into a pouring chamber up to a preset height level. When tapping, a shot pressure is supplied to the surface of the molten metal in the reservoir to raise the level of the molten metal in the pouring chamber to a pouring height over an in gate, and thus through a pouring sprue into a mold.
Typically, this kind of pouring furnace is successively fed a plurality of molding flasks just below the down sprue of the pouring furnace, and the shot pressure is supplied into the reservoir at a given timing, thereby pouring out a quantity of molten metal corresponding to the respective mold being filled.
In actuality, however, various molds have different pouring rates and, therefore, to control only the quantity of tapped metal is insufficient from the standpoint of optimum efficiency and automation of the pouring process. Usually, for this reason, after a sprue cup is filled with molten metal, it is required that the molten metal be supplied into the cup so as to keep the level of the metal constant. Thus, a pouring pattern employed by the present assignee herein may consists of a shot pressure, and a period of time during which the shot pressure is applied, each being selected according to the particular kind of mold. According to this kind of pouring pattern, a shot pressure .DELTA.p.sub.1 is applied during an initial period t.sub.1, and then a lower shot pressure .DELTA.p.sub.2 is applied during a subsequent period t.sub.2.
According to one process presently used by the assignee herein, the aforementioned pouring pattern is set manually. Hence, when molds, which are a few in number but various in kind, are supplied with molten metal from a single pouring furnace, a corresponding variety of pouring patterns must be set frequently, thus lowering operating efficiency and impeding the automation of the process.